PSY301 Midterm (Lecture 4) Questions with Detailed Verified Answers for Accuracy

ACCURACY IS GUARANTEED


PSY301 Midterm (Lecture 4) Questions with
Detailed Verified Answers for Accuracy
External Validity

✓✓ Extent to which the results of a study can be applied and
generalized to other people, settings, and situations


Internal Validity

✓✓ Allows you to conclude that the IV caused changes in the
DV


Threats to Internal Validity

✓✓ History, maturation, selection, interaction with selection,
mortality, testing, regression to the mean (statistical).


History

✓✓ Some event takes place between the testing of the levels of
the IV
Usually less of a concern in lab studies
More likely in longitudinal studies


Maturation

✓✓ Participants grow older/wiser, gain more experience
Most problematic with:
- Children (grow quickly)
- Long-term studies

, ACCURACY IS GUARANTEED

Selection

✓✓ People participating in the study are systematically
different from those not participating
Occurs in the absence of random selection and/or random
assignment


Interaction with Selection

✓✓ An interaction effect between maturation or history and
selection effects
- History or maturation may influence a subset of your
participants who are not randomly assigned


Mortality

✓✓ Dropping out of the experiment
A.k.a. "attrition"
Differential mortality: different kinds of participants drop out
of groups assigned to various levels of IV


Testing

✓✓ The act of testing can change behavior independently of
any other manipulation
Can be a threat when same questions are used multiple times
- But can also exist with cross-sectional study


Regression to the Mean